I'm trying to set up fastcgi_cache with nginx+php-fpm. I can see directories appearing in my cache dir, but pages that I expect to return a cached hit, are downloaded (0 kb files) rather than served as a web page. I can see why it might be the default_type setting, but I don't know what else to set it to, or how to override the setting inside the location block.
[code]
user www-data;
worker_processes 4;

error_log /var/log/nginx/error.log;
pid /var/run/nginx.pid;

events {
worker_connections 1024;
}

http {
server_names_hash_max_size 512;
server_names_hash_bucket_size 128;

index index.php index.html index.htm;

include mime.types;
default_type application/octet-stream;

fastcgi_cache_path /var/cache/nginx levels=1:2 keys_zone=WORDPRESS:10m inactive=5m;

access_log /var/log/nginx/access.log;
sendfile on;

keepalive_timeout 65;

gzip on;
gzip_disable "MSIE [1-6]\.(?!.*SV1)";

include /etc/nginx/conf.d/*.conf;
include /etc/nginx/sites-enabled/*;
}


server {
listen 127.0.0.1:80 default;
server_name www.mysite.com;

error_log /var/log/nginx/www.mysite.com-error.log;
access_log /var/log/nginx/www.mysite.com-access.log;

root /home/graq/sites/www.mysite.com;


location / {
try_files $uri $uri/ /index.php?q=$uri&$args;
}

location ~ \.php$ {
set $wordpress_logged_in "";
set $comment_author_email "";
set $comment_author "";

if ($http_cookie ~* "wordpress_logged_in_[^=]*=([^%]+)%7C") {
set $wordpress_logged_in wordpress_logged_in_$1;
}

if ($http_cookie ~* "comment_author_email_[^=]*=([^;]+)(;|$)") {
set $comment_author_email comment_author_email_$1;
}

if ($http_cookie ~* "comment_author_[^=]*=([^;]+)(;|$)") {
set $comment_author comment_author_$1;
}

set $my_cache_key "$scheme://$host$uri$is_args$args$wordpress_logged_in$comment_author_email$comment_author";

fastcgi_pass_header Set-Cookie;
fastcgi_cache_use_stale error timeout invalid_header http_500;
fastcgi_cache_key $my_cache_key;
fastcgi_cache WORDPRESS;
fastcgi_cache_valid 200 1m;

fastcgi_pass unix:/usr/local/var/run/php-fpm.sock;
fastcgi_index index.php;
fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
fastcgi_param PATH_INFO $fastcgi_script_name;
include fastcgi_params;
}
}

[/code]